YOKOGAWA WT3002E - Chapter 7 Harmonic Measurement in Normal Measurement Mode (Option); Harmonic Measurement Function

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IM WT3001E-51EN
Harmonic Measurement in Normal Measurement Mode (Option)
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Index
7.1 Harmonic Measurement Function
Harmonic measurement can be used to measure the harmonic components of the
voltage, current, and power as well as measurement functions such as the phase angle
of each harmonic order with respect to the fundamental signal. It can also be used to
compute the harmonic distortion of the voltage and current.
Harmonic Measurement Types
Three types of harmonic measurement below can be performed when the advanced
computation (/G6) option is installed in this instrument. Switch the measurement mode
according to your application.
• Harmonic Measurement in Normal Measurement Mode
Various functions such as integration, waveform display, trend display, and efficiency
computation can be used simultaneously with the harmonic measurement. In
addition, the rms voltage and current are the total of the rms values of all frequency
components in the measurement frequency bandwidth. This rms value and harmonics
can be measured simultaneously.
* This harmonic measurement does not conform to IEC 61000-3-2.
• Wide Bandwidth Harmonic Measurement Mode
Harmonic measurement up to 50
th
order can be performed on a signal with a 1-kHz
fundamental frequency. Use this mode for harmonic measurement of signals whose
fundamental frequency is higher than the commercial power supply frequency. By
applying an external sampling clock, harmonics can be measured on low frequency
signals with a fundamental frequency of 0.1 Hz. The harmonics of inverters that drive
motors at low frequency (low revolution) can be measured.
• IEC Harmonic Measurement Mode
This mode in combination with the Harmonic/Flicker Measurement Software sold
separately allows you to perform harmonic measurement conforming to IEC 61000-3-
2. Use this mode to check that the harmonics of electric home appliances and office
automation equipment comply with the IEC standards.
100
50
0
0.1 1 10 100 1000
Harmonic measurement
in normal measurement
mode
Wide bandwidth harmonic
measurement
(Synchronized to PLL)
Wide bandwidth harmonic
measurement
(Synchronized to Smp Clk)
Fundamental frequency of the PLL source
IEC harmonic
measurement
Measured order
Measurement frequency and order in each measurement mode on models with the
advanced computation (/G6) option (when the anti-aliasing filter is OFF)
Chapter 7 Harmonic Measurement in Normal Measurement Mode (Option)